Suture anchor system with threaded plug

ABSTRACT

A suture anchor system including an anchor, a plug and an inserter. The anchor inserter includes a tubular outer shaft having a cannulation dimensioned to receive an inner shaft. The distal end of the outer shaft cannulation is threaded for engagement with the plug. The anchor includes a longitudinal cannulation formed within the anchor body, including a smooth-sided portion and a threaded portion. An eyelet, dimensioned to receive a suture therein, extends transverse to the longitudinal axis of the anchor and intersects the distal portion of the cannulation. The plug is a generally elongated, tubular threaded rod comprising a cannulation adapted to receive a distal end of the inner inserter shaft.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.15/738,329 filed Dec. 20, 2017, which is a U.S. 371 Application ofInternational Application No. PCT/US2015/038460, filed Jun. 30, 2015,entitled “SUTURE ANCHOR SYSTEM WITH THREADED PLUG.”

BACKGROUND

Arthroscopy surgery is a minimally-invasive surgery that involves therepair of tissue inside or around a joint. In shoulder arthroscopy, forexample, common injuries include a torn or damaged cartilage ring orligaments (causing shoulder instability), a torn rotator cuff, or a tornor damaged biceps tendon. Each of these injuries necessitates thereattachment of soft tissue (that is, the ligaments or tendons) to bone.

Suture anchors and suture anchor systems are useful fixation devices forfixing tendons and ligaments to bone. A typical suture anchor isinserted into the bone by pounding the suture anchor into the bone or byway of a bone hole using an anchor inserter. The suture anchor can beconfigured as a screw mechanism or an interference fit device and may bemade of metal, plastic or bioabsorbable material (which dissolves in thebody over time). The suture anchor can include an eyelet that allows oneor more sutures to pass therethrough and link the suture anchor and thesuture.

During the anchor insertion process, it is difficult for a surgeon toachieve linear stability of the suture anchor while it is coupled to amating, disposable inserter. Currently, an additional suture which iswrapped through the anchor and cleated to the inserter handle is oftenused to achieve linear stability. This method creates an additionalstrand of suture which can gets in a surgeon's way during a procedure.Other suture anchors are couple to inserters with press fits or othersuture constructs which also may cause obstruction.

SUMMARY

Accordingly, there is a need for a suture anchor system and method tofix an anchor to an inserter before insertion into bone, and to releasethe anchor from the inserter after completion, without adding additionalsteps for the surgeon. Additional advantages of such a system would besuperior fixation force, and a streamlined design that would be morecost-effective to manufacture than current suture anchor systems.

Described herein is a suture anchor system including an anchor inserter,a corresponding suture anchor, and a plug adapted for transfer from theanchor inserter to the anchor.

In one example, a suture anchor system of this disclosure caninclude: 1) an inserter having an elongated, cannulated outer shaftextending between a proximal end and a distal end, a distal end of theouter shaft being threaded; 2) an anchor having an elongated anchor bodyextending longitudinally between a proximal end and a distal end, aclosed eyelet, extending transversely through a longitudinal axis of theanchor, and dimensioned to receive one or more sutures, and acannulation formed within the anchor body and intersecting the eyelet,the cannulation including a proximal cannulation portion extendingdistally from the proximal end of the anchor body to a firstlongitudinal position proximal to the eyelet, and a threaded distalcannulation portion extending distally from the first longitudinalposition to a second longitudinal position distal to the eyelet; and 3)a threaded, tubular plug having a longitudinal cannula extending betweena proximal end and a distal end. The inner shaft of the inserter may beengageable with the cannula of the plug to move the plug distally withrespect to the anchor from a first axial position to a second axialposition. In the first axial position, the plug can engage both theanchor body and the outer shaft of the inserter and a distal terminus ofthe plug may be proximal to the eyelet. In the second axial position,the plug can engage the anchor body, but not the outer shaft of theinserter, and the distal terminus of the plug can abut a distal terminusof the anchor body cannulation. The inserter can be made of any type ofmetal. A diameter of the distal end of the inserter can be smaller thana diameter of the rest of the inserter. A size of the distal end of theinserter may be selected to couple with the proximal cannulation portionof the anchor. The anchor can be made of one of a plastic, abioabsorbable material and/or a metal. The distal end of the anchor bodymay be closed. The proximal cannulation portion of the anchor can benon-threaded. Moving the plug distally with respect to the anchor mayincludes rotating the inner shaft of the inserter. The plug can be madeof any one of a plastic, a bioabsorbable material and/or a metal. A pluglength may be between about 5 mm and about 8.5 mm and a plug diametermay be between about 1.9 mm and about 2.1 mm.

In another example, a method of securing a suture of this disclosure caninclude: 1) routing a suture through an eyelet dimensioned to receiveone or more sutures extending transversely through a longitudinal axisof an anchor, the anchor further having an elongated anchor bodyextending longitudinally between a proximal end and a distal end and acannulation formed within the anchor body and intersecting the eyelet,the cannulation including a proximal cannulation portion extendingdistally from the proximal end of the anchor body to a firstlongitudinal position proximal to the eyelet, and a threaded distalcannulation portion extending distally from the first longitudinalposition to a second longitudinal position distal to the eyelet; 2)engaging a distal end of a threaded, tubular plug with the distalcannulation portion of the anchor, the plug further having alongitudinal cannula extending between a proximal end and a distal end;3) engaging a proximal end of the plug with a threaded distal end of acannulation of an outer shaft of an inserter, the inserter furtherhaving an elongated inner shaft extending between a proximal end and adistal end, the inner shaft being dimensioned for receipt within andaxially moveable independent of the outer shaft; 4) inserting thethreaded distal end of the cannulation of the outer shaft of theinserter within the proximal cannulation portion of the anchor; and 5)engaging the inner shaft of the inserter with the cannula of the plug tomove the plug distally with respect to the anchor from a first axialposition, where the plug engages both the anchor body and the outershaft of the inserter and a distal terminus of the plug is proximal tothe eyelet, to a second axial position, where the plug engages theanchor body but not the outer shaft of the inserter and the distalterminus of the plug abuts a distal terminus of the anchor bodycannulation, whereby the suture is secured between the distal terminusof the plug and the distal terminus of the anchor body cannulation. Themethod may further include removing the inserter from the anchor.

The advantages of this design is a streamlined device assembly in aneat, contained and reliable fashion, and may present cost benefitsduring manufacture. Furthermore, this form of fixation is far superiorthan other systems in terms of fixation force. Finally, the total numberof steps in a surgical procedure is reduced, since there is no need toremove an extra suture.

For a better understanding of the present disclosure, together withother and further needs thereof, reference is made to the accompanyingdrawings and the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other objects, features and advantages of theinvention will be apparent from the following more particulardescription of the examples, as illustrated in the accompanyingdrawings, in which:

FIG. 1A is an exploded view of an example of the suture anchor system ofthis disclosure;

FIG. 1B is an isometric view of an example of the inserter of FIG. 1A;

FIGS. 2A and 2B are illustrations of further examples of the sutureanchor system of this disclosure;

FIGS. 2C and 2D are illustrations of an example of the method of usingthe suture anchor system of this disclosure; and

FIG. 3 is an alternative example of the suture anchor system of thisdisclosure.

DETAILED DESCRIPTION

In the description that follows, like components have been given thesame reference numerals, regardless of whether they are shown indifferent examples. To illustrate an example(s) of the present inventionin a clear and concise manner, the drawings may not necessarily be toscale and certain features may be shown in somewhat schematic form.

Features that are described and/or illustrated with respect to oneexample may be used in the same way or in a similar way in one or moreother examples and/or in combination with or instead of the features ofthe other examples.

As used in the specification and in the claims, the singular form of“a”, “an”, and “the” include plural referents unless the context clearlydictates otherwise.

As used in the specification and in the claims, for the purposes ofdescribing and defining the invention, the terms “about” and“substantially” are used represent the inherent degree of uncertaintythat may be attributed to any quantitative comparison, value,measurement, or other representation. The terms “about” and“substantially” are also used herein to represent the degree by which aquantitative representation may vary from a stated reference withoutresulting in a change in the basic function of the subject matter atissue.

Referring now to FIG. 1A, an exploded, cross-sectional view of anexample of the suture anchor system 100 of this disclosure is shown. Thesuture anchor system 100 generally includes a suture anchor 102, athreaded plug 104, and an inserter 106. The suture anchor 102 can have asolid, hard barb design, as shown in FIG. 1A, although other anchordesigns are possible. The suture anchor 102 can also be a pound indevice or a screw in device. The suture anchor 102 may be completely, orportions thereof, made from a formulation of poly(lactic-co-glycolic)acid (PLGA), B-Tricalcium phosphate (B-TCP) and calcium sulfate,poly-L-lactic acid-hydroxyapatite (PLLA-HA), poly-D-lactide (PDLA),polyether ether ketone (PEEK) or variants thereof. Biocompositeembodiments of the suture anchor made from a combination of PLGA, B-TCP,and calcium sulfate are absorbable by the body, which is beneficial tonatural healing. An example formulation of PLGA, B-TCP, and calciumsulfate is described in U.S. Pat. No. 8,545,866, the entirety of whichis herein incorporated by reference. Other commonly used material forsuture anchors are also contemplated by this disclosure.

The threaded plug 104 of the suture anchor system 100 is substantiallytubular and includes a cannula 126 extending from a proximal to a distalend. A plug length may be between about 5 mm and about 8.5 mm. A plugdiameter may be between about 1.9 mm and about 2.1 mm. The plug 104 maybe fully threaded about its surface or, as shown in FIG. 1A, may have adistal portion that is unthreaded. The plug 104 may be made of aplastic, metal, or bioabsorable material. The distal end of the plug 104may be open and in communication with the cannula 126 or may beclosed-ended. The cannula 126 may extend distally through the entirelength of the plug 104 or to any functional distance proximal thereto.The cannula 126 is dimensioned to receive an inner shaft 112 of theinserter 106, as further described below.

The inserter 106 of the suture anchor system 100 includes an elongated,cannulated outer shaft 108 extending between a proximal end and a distalend of the inserter 106. An inner surface of a distal end 124 of theouter shaft 108 further has threads 110 to engage the threads of theplug 104. A diameter of the distal end 124 is smaller than a diameter ofany portion of the rest of the inserter 106, so that when the distal endof the outer shaft 108 is inserted into the anchor 102 (as describedbelow), the anchor is fully seated against the rest of the inserter 106.The inserter 106 also has an elongated inner shaft 112 extending betweena proximal end and a distal end of the inserter 106. The inner shaft 112is dimensioned for receipt within the outer shaft 108 and is axiallymoveable independent of the outer shaft 108. FIG. 1B is an isometricview of the inserter 106, further illustrating the threads 110 on theinner surface of the distal end 124. The inserter 106, including theouter shaft 108 and inner shaft 112, can be made from any type of metalor other suitable material.

Referring now to FIGS. 2A and 2B, the suture anchor 102 includes anelongated anchor body 114 extending longitudinally between a proximalend and a closed distal end. The suture anchor 102 also has a closedeyelet 116, extending transversely through a longitudinal axis of theanchor 102, and dimensioned to receive one or more sutures (not shown).The anchor 102 further includes a suture anchor cannulation 118 formedwithin the anchor body 114 and intersecting the eyelet 116. The sutureanchor cannulation 118 has a smooth-sided (e.g. non-threaded) proximalcannulation portion 120 extending distally from a proximal end (P) ofthe anchor body 114 to a first longitudinal position (L₁) proximal tothe eyelet 116, and a threaded distal cannulation portion 122 extendingdistally from the first longitudinal position (L₁) to a secondlongitudinal position (L₂) distal to the eyelet 116. FIG. 2A shows thethreaded plug 104 joining the anchor 102 to the inserter 106, as furtherdescribed below. FIG. 2B shows the threaded plug 104 no longer joiningthe anchor 102 to the inserter 106, as further described below.

In use, as shown in FIG. 2C, the anchor 102 is mounted to the inserter106 by means of the threaded plug 104, which is engaged with both theanchor 102 and the inserter 106, as described herein. A suture 128 maybe first routed through the eyelet 116. The threaded distal end 124 ofthe outer shaft 108 of the inserter 106 is inserted within the proximalcannulation portion 120 of the anchor 102. The distal end of thethreaded plug 104 is engaged with the distal cannulation portion 122 ofthe anchor 102 while the proximal end of the threaded plug 104 isengaged with the threads 110 of the distal end 124 of the outer shaft108. This position defines a first axial position wherein the threadedplug 104 engages both the anchor body 114 and the outer shaft 108 of theinserter 106 and the distal terminus of the threaded plug 104 isproximal to the eyelet 116. So positioned, the threaded plug 104advantageously secures the anchor 102 to the inserter 106 and alsoprovides a bridge for transmission of force between the anchor 102 andinserter 106 during the anchor insertion process. In addition, thisarrangement means that there is less opportunity for a surgeon toaccidentally knock the anchor 102 off of the inserter 106. The surgeonwill therefore be able to advance the suture anchor system 100 in andout of a surgical cannula more reliably.

As shown in FIG. 2D, after insertion of the anchor 102 into a bone holeof a patient (not shown), the suture 128 is secured to the anchor 102,as described herein. The inner shaft 112 of the inserter 106 is distallyadvanced through the cannula 126 of the threaded plug 104 by rotation ofthe inner shaft 112 by a means of a part of a handle attached to theinserter 106 (not shown). Additional distal advancement of the innershaft 112 to the distal end of the cannula 126 urges the threaded plug104 distally into the distal cannulation portion 122. The suture 128 isthen secured between a distal terminus of the threaded plug 104 and thedistal terminus of the suture anchor cannulation 118. The distaladvancement of the threaded plug 104 further positions the threaded plug104 fully within the anchor 102 and unengaged with the inserter 106.This position defines a second axial position, wherein the threaded plug104 engages the anchor body 114 but not the outer shaft 108 of theinserter 106, and the distal terminus of the threaded plug 104 abuts thedistal terminus of the anchor body cannulation 118. Accordingly, theinserter 106 (both the inner shaft 112 and outer shaft 108) is fullyretracted from the anchor 102, leaving the anchor 102, the threaded plug104, and the suture 128 secured to the bone hole.

FIG. 3 shows an alternative example of the suture anchor system of thisdisclosure. As shown in FIG. 3, the geometry of the anchor 304, the plug302 and the outer shaft 308 can be manipulated to the point where theplug 302 can sit within the outer shaft 308, yet still perform the samefunction.

Although the invention has been described with respect to variousembodiments, it should be realized this invention is also capable of awide variety of further and other embodiments within the spirit andscope of the appended claims.

1. A suture anchor system, comprising: an inserter including a shaftwith a cannulated distal end, the cannulated distal end including athreaded portion; and an anchor, comprising: an eyelet, extendingtransversely through a longitudinal axis of the anchor dimensioned toreceive one or more sutures; a cannulation extending along thelongitudinal axis of the anchor, the cannulation including a threadedportion; and a plug having a threaded external surface that threadinglycouples directly to both the shaft threaded portion and anchorcannulation threaded portion, and thereby operatively couples the anchorto the inserter.
 2. The suture anchor system of claim 1, wherein theplug is also configured to advance axially along the anchor cannulationto threadingly disengage from the inserter and at least partiallyocclude the eyelet.
 3. The suture anchor system of claim 1, wherein theanchor cannulation also includes a non-threaded portion.
 4. The sutureanchor system of claim 1, wherein the anchor and the shaft distal endare also telescopically mated with each other.
 5. The suture anchorsystem of claim 1, wherein the distal end of the shaft is coextensivewith the anchor independent of a position of the plug.
 6. The sutureanchor system of claim 1, wherein the anchor and anchor is comprised ofa plastic, a bioabsorbable material or a metal.
 7. The suture anchorsystem of claim 1, wherein the plug has a distal non-threaded portion.8. The suture anchor system of claim 1, wherein the inserter furthercomprises an inner shaft, axially moveably within the inserter shaft andconfigured to advance the plug distally with respect to the anchor byrotating.
 9. A suture anchor system, comprising: an inserter including ashaft with an internally threaded cavity at an inserter distal end; andan anchor, comprising: an eyelet, extending transversely through alongitudinal axis of the anchor for receiving one or more suturestherethrough; a cannulation extending along the longitudinal axis of theanchor, the cannulation including a threaded portion; and a threadedplug configured to threadingly couple the anchor to the inserterinternally threaded cavity and wherein the plug is also configured toadvance axially along the anchor cannulation to both threadinglydisengage the anchor from the inserter and at least partially secure theone or more sutures within the eyelet.
 10. The system of claim 9 whereinthe inserter distal end is also configured to telescopically couple withthe anchor.
 11. The system of claim 9 wherein threadingly coupling theplug directly to both the anchor and inserter provides a forcetransmission bridge between the anchor and inserter so as to providelinear stability to the system and thereby replacing an auxiliarycoupling suture connecting the anchor and the inserter.
 12. The systemof claim 9 wherein the plug is further configured to advance axially andat least partially extend across the eyelet.
 13. The suture anchorsystem of claim 9, wherein the inserter further comprises an innershaft, axially moveably within the inserter shaft and configured toadvance the plug distally with respect to the anchor by rotating. 14.The suture anchor system of claim 9, wherein the inserted distal end iscoextensive with the anchor, independent of a position of the plug. 15.A suture anchor system, comprising: an inserter including a shaft with acannulated distal end, the cannulated distal end including a threadedportion for selectively threadingly coupling directly with threads of ananchor plug; and an anchor, comprising: an eyelet, extendingtransversely through a longitudinal axis of the anchor dimensioned toreceive one or more sutures; a cannulation extending along thelongitudinal axis of the anchor, the cannulation including a threadedportion for threadingly coupling to the anchor plug threads.
 16. Thesuture anchor system of claim 15, wherein the anchor and the shaftdistal end are telescopically engaged with each other.
 17. The sutureanchor system of claim 15 wherein the distal end of the shaft isconfigured to coextensively mate with the anchor.
 18. The system ofclaim 15 wherein when the inserter is threadingly coupled to the plug,the plug provides a force transmission bridge between the anchor andinserter so as to gain linear stability.
 19. The system of claim 15wherein the plug is further configured to advance axially, disengagewith the threaded portion of the inserter and secure a length of suturewith the anchor.
 20. The suture anchor system of claim 15, wherein theinserter further comprises an inner shaft, axially moveably within theinserter shaft and configured to advance the plug distally.